The present invention relates to bismuth-containing pharmaceutical compositions suitable for oral administration to humans or lower animals. This invention also relates to methods for treating or preventing disturbances of the gastrointestinal tract by administering a composition of the present invention.
Bismuth-containing pharmaceutical compositions are well known, being used widely to treat a variety of gastrointestinal disorders such as nausea, heartburn, and diarrhea. One such product is liquid Pepto-Bismol (sold by The Procter & Gamble Company). This product contains bismuth/subsalicylate and a methylcellulose/magnesium aluminum silicate suspension system. Another is Pabizol with Paregoric (sold by Rexall) which is a liquid suspension said to contain, in addition to opium, bismuth subsalicylate (17.0 mg/ml), aluminum magnesium silicate (8.83 mg/ml), and hydroxypropylmethylcellulose (6.7 mg/ml). These and other bismuth-containing compositions are described generally in "Handbook of Nonprescription Drugs, 8th Edition" (American Pharmaceutical Association, Washington, D.C.; 1986), pages 73-74, the disclosures of which are incorporated herein by reference in their entirety.
Notwithstanding the great effort already put forth to identify bismuth-containing compositions, there remains a continuing need to identify new compositions which have improved pharmaceutical properties. The bismuth-containing pharmaceutical compositions of the present invention have such improved properties, including being surprisingly more effective for coating the gastrointestinal tract.
Thus, an object of the present invention is to provide bismuth-containing pharmaceutical compositions which are effective for coating the gastrointestinal tract. Another object is to provide compositions suitable for oral administration which are effective for treating or preventing disturbances of the gastrointestinal tract. An object of the present invention is also to provide bismuth-containing compositions effective for delivering higher doses of bismuth-containing agents to the gastrointestinal tract. A further object is to provide pharmaceutical compositions containing bismuth-containing agents having enhanced efficacy. Finally, an object is to provide methods for treating or preventing disturbances of the gastrointestinal tract in humans or lower animals.
These and other objects of the present invention will become readily apparent from the detailed description which follows.
All percentages and ratios used herein are by weight unless otherwise specified.